The present invention relates generally to methods and systems for performing medical procedures and relates more particularly to a new method and system for performing a medical procedure.
There are many types of situations in which it is desirable for a medical procedure to be performed on a patient. Such a procedure may be diagnostic and/or therapeutic in nature. For example, in the field of gynecology, one may wish to examine and/or treat a uterus for various abnormal conditions including, but not limited to, the presence of fibroids, polyps, tumors, adhesions, or other abnormalities within a uterus; endometriosis or other abnormal bleeding; uterine prolapse; ectopic pregnancy; and fertility issues (both the inability to conceive and the desire to avoid pregnancy).
The uterus is a pear-shaped organ made up two distinct anatomical regions: the cervix and the corpus. The cervix is a narrow cylindrical passage (about 1.5-4.0 mm in diameter) which connects at its lower end with the vagina. The corpus, which is the portion of the uterus that grows during pregnancy to carry a fetus, is shaped to include two portions: the lower uterine segment and the fundus. The cervix widens at its upper end to form the lower uterine segment of the corpus. The lower uterine segment, in turn, widens at its upper end into the fundus of the corpus. Dimensionally, the length of the uterus, measured from the cervix to the fundus, is approximately 8-10 cm, and the maximum width of the uterus, which is near the fundus, is about 4-5 cm. Extending from the fundus of the uterus on either side are fallopian tubes. The fallopian tubes are continuous with the uterine cavity and allow the passage of an egg from an ovary to the uterus where the egg may implant if fertilized.
To facilitate the examination and/or treatment of the uterus, there should be ample space within the uterus. Unfortunately, however, adequate space typically does not exist naturally in the uterus because the uterus is a flaccid organ. As such, the walls of the uterus are typically in contact with one another when in a relaxed state. Consequently, active steps need to be taken to create a working space within the uterus.
The conventional technique for creating such a working space within the uterus is to administer a fluid to the uterus, transcervically, under sufficient pressure to cause the uterus to become distended. Examples of the fluid used conventionally to distend the uterus include gases like carbon dioxide and liquids like water or certain aqueous solutions (e.g., a saline solution or a sugar-based aqueous solution).
With the uterus thus distended, examination of the uterus is typically performed using a hysteroscope—a visualization device that is inserted transcervically into the uterus. If fibroids (i.e., benign tumors), polyps or other abnormalities are detected, such abnormalities may be removed, for example, by resection. Certain devices include the combination of visualization means, such as a hysteroscope, and resection means, such as a morcellator. Examples of such devices are disclosed in U.S. Pat. No. 6,032,673, inventor Savage et al., issued Mar. 7, 2000; U.S. Pat. No. 5,730,752, inventors Alden et al., issued Mar. 24, 1998; and PCT International Publication Number WO 99/11184, published Mar. 11, 1999.
Although the above-described technique of fluid distension is commonly practiced, there are certain shortcomings associated therewith. For example, because the distending fluid is administered under pressure (which pressure may be as great as 120 mm Hg or greater), there is a risk that such fluids may be taken up by a blood vessel in the uterus, i.e., intravasation, which uptake may be quite harmful to the patient. Because the risk of excess intravasation can lead to death, it is customary to monitor the fluid uptake on a continuous basis using a scale system. This risk of excess intravasation is particularly great when the fluid distension technique is followed by a procedure in which a blood vessel is cut, such as when abnormal or undesired tissue located in the uterus is resected.
Moreover, the above-described technique of fluid distension suffers from additional shortcomings. For example, throughout the entire period of time that the diagnostic and/or therapeutic procedure is performed, the distension fluid must be continuously administered under pressure to the patient to keep the uterus distended. This requires the availability of an adequate supply of the distending fluid. In addition, suitable equipment must be available to provide the requisite continuous flow of distending fluid to the patient. Furthermore, the above-described fluid distension technique may become messy, particularly when a liquid is used as the distension fluid, as some of the distension fluid within the uterus may escape proper collection and, instead, may leak from the patient to the surrounding environment.
For at least the above reasons, medical procedures involving fluid distension of the uterus are typically performed in a hospital and, as a result, bear a large cost due to the setting and the support personnel required.